ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
551 
by Sorauer, rudimentary peritlieces. They appear to be special organs, 
of the nature of sclerotes, whose purpose is to enable the parasitic 
fungus to force its way into the tissues of its host. 
Discomycetes.* — Herr K. Starbiick proposes the following ter- 
minology for the various parts of the excipule of the Discomycetes : — 
The entire outer layer is the pars parietis excipuli ; the portion which 
surrounds the hymenium and the epithece is the margo excipuli and pars 
marginalis excipuli ; the inner portion lying beneath the hypothece is 
thenars fundi excipuli; when the separate hyphse are not distinguish- 
able, the tissue is a textura globosa if the cells arc nearly isodiametric, 
textura prismatica if the cells are not isodiametric ; when the separate 
kyphte are easily distinguishable, the tissue is a textura intricata when 
the kyphre run in all directions and their walls are not coalescent, tex- 
tura epidermoidea if the walls are more or less confluent ; textura oblita 
when the kyphm run nearly parallel and have small cavities with 
strongly thickened walls, textura porrecta if the hypliae have large 
cavities and their walls not thickened. 
The author points out the near relationship of Pezizella to 3Iollisia, 
and proposes the division of the former genus into two subgenera, 
Eupezizella and Ctenoscypha. 
Classification of Lichens.f — Herr J. Reinke regards the Crustaceous 
as probably the oldest form of Lichens, from which the Foliaceous and 
the Fruticose forms have descended. He proposes the division of the 
whole group into 3 sub-classes, viz. : — (1) The Coniocarpi, corre- 
sponding to the Caliciaceae of Tuckermann, and derived from the Proto- 
caliciaceae among Fungi. It is divided into the two families, Caliciacei 
and Acoliacei ; (2) Discocarpi, including by far the greatest number of 
the Lichens, characterised by saucer- or disc-shaped apotheces. This is 
divided into 4 series — the Grammopliori (Graphidacei and Xylographacei), 
Lecideales (Gyalectacei, Lecideacei, Umbiiicariacei, and Cladoniacei), 
Parmeliales (Urceolariacei, Pertusariacoi, Parmeliacei, Physciacei, The- 
loschistacei, and Acarosporacei), and Cyanophili (Licliinacei, Ephebacei, 
Pannariacei, Stictacei, Peltigeracei, Collemacei, and Omphalariacei). 
(3) The Pyrenocarpi, with pitcher-shaped apotheces, comprising only 
the Verrucariacei. A conspectus of all the known genera follows. 
Phylogenetic Adaptations of Lichens.^ — Mr. A. Schneider de- 
scribes some of the adaptations which have been fixed by heredity, by 
which lichens have adapted themselves to their peculiar biological con- 
ditions. A typical epidermal layer is well developed in Stida and 
Stidina. For the purpose of aeration, a number of intercellular canals 
frequently pass from the algal layer through the cortical and epidermal 
layers; in a dry state these canals are practically closed. They are 
especially numerous in Nephromium , Solorina, and Parmelia. In other 
genera, especially Sticta and Stidina, we find the structures known as 
cyphellse, which also probably serve for the aeration of the algal con- 
* Bih. Svensk. Vetensk.-Akad. Hand!., xxi. (1895) 42 pp. and 2 pis. See Bot. 
Centralbl., lxvi. (1896) p. 345. 
f Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger) xxix. (1896) pp. 171-236 (14 figs.). 
Of. this Journal, ante , p. 217. 
% Bull. Torrey Bot. Club, xxii. (1895) pp. 494-500. 
